Fuel Cells — Predicted 2026

AI-Predicted Question Angles for UPSC 2026

Based on trend analysis, current affairs, and recurring themes in Fuel Cells.

Identification of Electrode Reactions and Products

high

This is a fundamental aspect of fuel cells and electrochemistry. NEET frequently tests the ability to correctly identify what happens at the anode (oxidation of fuel) and cathode (reduction of oxidant) and the final products. For the H2-O2 fuel cell, knowing that hydrogen is oxidized to protons (or water in alkaline medium) and oxygen is reduced to water (or hydroxide in alkaline medium) is crucial. Questions might ask for the specific half-reactions or the overall reaction, or simply the byproduct.

Distinction between Fuel Cells and Batteries

high

This is a classic comparative question type. Students are expected to understand the key differences, particularly the continuous supply of reactants in fuel cells versus the internal, finite reactants in batteries. The 'no recharging' aspect of fuel cells is a common point of distinction. Questions will likely present scenarios or statements and ask to identify the correct differentiating factor.

Thermodynamic Calculations (ΔG and Efficiency)

medium

While less frequent than conceptual questions, numerical problems involving $Delta G = -nFE_{cell}$ or the theoretical efficiency formula ($eta = |Delta G|/|Delta H|$) are possible. These questions test the application of electrochemical thermodynamics. Aspirants should be able to determine 'n' (number of electrons transferred) for the overall reaction and perform basic calculations. The values for $E_{cell}$, $Delta G$, or $Delta H$ might be given, and the student would need to calculate the unknown.

Environmental Impact and Advantages

medium

Given the increasing emphasis on environmental science and sustainable development, the eco-friendly nature of fuel cells (especially hydrogen fuel cells producing only water) is a significant point. Questions might focus on why fuel cells are considered 'green technology' or compare their emissions with conventional combustion engines. This tests conceptual understanding of their broader societal impact.